:root {
  --bg: #fbfbf9;
  --surface: #ffffff;
  --ink: #1b1d22;
  --muted: #5d636e;
  --line: #e3e3de;
  --accent: #2f5bff;
  --accent-soft: rgba(47, 91, 255, 0.10);
  --logo-accent: #2f5bff;
  --good: #1a7f37;
  --bad: #c0362c;
  --code-bg: #f2f2ee;
  --chart-muted: #b7b9b0;
  --chart-grid: #e6e6e1;
  --chart-axis: #8f939a;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1115;
    --surface: #171a20;
    --ink: #e7e9ee;
    --muted: #9aa1ad;
    --line: #2a2f38;
    --accent: #7d97ff;
    --accent-soft: rgba(125, 151, 255, 0.14);
    --logo-accent: #5a7bff;
    --good: #4cc26b;
    --bad: #ff7a6e;
    --code-bg: #1d2129;
    --chart-muted: #5d636e;
    --chart-grid: #262b33;
    --chart-axis: #7d838e;
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB",
    "Noto Sans SC", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.75;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.wrap { max-width: 880px; margin: 0 auto; padding: 0 20px; }

/* top bar — sized against Sakana (80px), Anthropic (84px), Together (60px), Thinking Machines (54px) */
.topbar { background: var(--bg); }
.topbar .wrap { display: flex; align-items: center; justify-content: space-between; height: 72px; gap: 24px; }
.brand { font-weight: 650; font-size: 18px; letter-spacing: -0.2px; color: var(--ink); display: flex; align-items: center; gap: 10px; }
.brand:hover { text-decoration: none; }
.brand-mark { width: 48px; height: 48px; object-fit: contain; flex: none; }
.nav { display: flex; align-items: center; gap: 28px; font-size: 15px; }
.nav a { color: var(--muted); }
.nav a:hover, .nav a.on { color: var(--ink); text-decoration: none; }

/* hero */
.hero { padding: 72px 0 40px; }
.hero h1 { font-size: 40px; line-height: 1.25; margin: 0 0 16px; letter-spacing: -0.5px; }
.hero p.lead { font-size: 19px; color: var(--muted); margin: 0; max-width: 680px; }
.eyebrow { font-size: 13px; font-weight: 600; letter-spacing: 1.2px; text-transform: uppercase; color: var(--accent); margin-bottom: 14px; }

section { padding: 28px 0; }
section > h2, .doc h2 { font-size: 24px; margin: 48px 0 12px; padding-top: 8px; letter-spacing: -0.2px; }
.doc h2 { border-top: 1px solid var(--line); padding-top: 32px; }
.doc h1 { font-size: 34px; line-height: 1.3; margin: 56px 0 8px; letter-spacing: -0.4px; }
.doc h3 { font-size: 18px; margin: 32px 0 8px; }
.meta { color: var(--muted); font-size: 14px; margin: 0 0 24px; }

/* cards */
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px; margin-top: 16px; }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: 10px; padding: 20px; }
.card h3 { margin: 0 0 6px; font-size: 17px; }
.card p { margin: 0; color: var(--muted); font-size: 15px; line-height: 1.65; }
.card .tag { display: inline-block; font-size: 12px; font-weight: 600; padding: 2px 8px; border-radius: 999px; margin-bottom: 10px; background: var(--accent-soft); color: var(--accent); }
.card .tag.todo { background: var(--code-bg); color: var(--muted); }
a.card { display: block; color: inherit; transition: border-color .15s; }
a.card:hover { border-color: var(--accent); text-decoration: none; }

.stats { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 12px; margin: 20px 0 8px; }
.stat { background: var(--surface); border: 1px solid var(--line); border-radius: 10px; padding: 16px; }
.stat b { display: block; font-size: 26px; line-height: 1.2; }
.stat span { font-size: 13px; color: var(--muted); }

/* doc content */
.doc { padding-bottom: 80px; }
.doc p, .doc li { font-size: 16px; }
.doc ul, .doc ol { padding-left: 22px; }
.doc li { margin: 4px 0; }
.table-scroll { overflow-x: auto; margin: 16px 0; -webkit-overflow-scrolling: touch; }
table { border-collapse: collapse; width: 100%; font-size: 14px; background: var(--surface); }
th, td { border-bottom: 1px solid var(--line); padding: 8px 10px; text-align: left; vertical-align: top; }
th { font-weight: 600; background: var(--code-bg); white-space: nowrap; }
code { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 0.88em; background: var(--code-bg); padding: 1px 5px; border-radius: 4px; }
pre { background: var(--code-bg); padding: 14px 16px; border-radius: 8px; overflow-x: auto; font-size: 13px; line-height: 1.6; }
pre code { background: none; padding: 0; }
blockquote { margin: 16px 0; padding: 4px 16px; border-left: 3px solid var(--accent); color: var(--muted); }

figure { margin: 24px 0; }
figure svg { width: 100%; height: auto; display: block; }
figcaption { font-size: 13px; color: var(--muted); margin-top: 8px; }

.toc { background: var(--surface); border: 1px solid var(--line); border-radius: 10px; padding: 14px 20px; margin: 24px 0; font-size: 15px; }
.toc ol { margin: 6px 0 0; padding-left: 20px; }

footer { border-top: 1px solid var(--line); color: var(--muted); font-size: 13px; padding: 24px 0 40px; }

@media (max-width: 600px) {
  .hero { padding: 48px 0 24px; }
  .hero h1 { font-size: 30px; }
  .hero p.lead { font-size: 17px; }
  .doc h1 { font-size: 27px; }
  .topbar .wrap { height: 60px; gap: 12px; }
  .brand { font-size: 16px; gap: 8px; }
  .brand-mark { width: 40px; height: 40px; }
  .nav { gap: 16px; font-size: 14px; }
  .nav .gh { display: none; }
}

/* home: lab-style landing */
.hero.home { padding: 112px 0 72px; }
.hero.home h1 { font-size: 56px; line-height: 1.15; letter-spacing: -1px; margin-bottom: 24px; }
.hero.home p.lead { font-size: 19px; max-width: 620px; }
.section-title { font-size: 13px !important; font-weight: 600; letter-spacing: 1.4px; color: var(--muted); text-transform: uppercase; margin: 24px 0 8px !important; }
.posts { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--line); }
.posts li { border-bottom: 1px solid var(--line); }
.posts a { display: grid; grid-template-columns: 96px 1fr; gap: 20px; padding: 24px 0; color: inherit; }
.posts a:hover { text-decoration: none; }
.posts a:hover .post-title { color: var(--accent); }
.post-date { color: var(--muted); font-size: 14px; padding-top: 3px; font-variant-numeric: tabular-nums; }
.post-body { display: block; }
.post-title { display: block; font-size: 20px; font-weight: 600; line-height: 1.4; margin-bottom: 8px; transition: color .15s; }
.post-desc { display: block; color: var(--muted); font-size: 15px; line-height: 1.7; }
.post-tags { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 12px; }
.post-tags span { font-size: 12px; padding: 2px 10px; border: 1px solid var(--line); border-radius: 999px; color: var(--muted); }
.about { max-width: 640px; color: var(--ink); }
@media (max-width: 600px) {
  .hero.home { padding: 64px 0 40px; }
  .hero.home h1 { font-size: 36px; }
  .posts a { grid-template-columns: 1fr; gap: 6px; }
}

/* framework bits */
.nav .lang { border: 1px solid var(--line); border-radius: 999px; padding: 2px 12px; color: var(--ink); line-height: 1.5; }
footer .wrap { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; }
footer a { color: var(--muted); }
.empty { color: var(--muted); padding: 20px 0; border-top: 1px solid var(--line); margin: 0; }
.back { margin: 32px 0 0; font-size: 14px; }
.doc .post-tags { margin: 0 0 24px; }

/* Research stories: a readable article with a quiet, sticky contents rail. */
.research-article { max-width: 1120px; }
.research-header { max-width: 840px; margin: 56px 0 44px; }
.research-header .eyebrow { margin: 0 0 16px; }
.research-header h1 { font-size: clamp(32px, 4.2vw, 48px); line-height: 1.16; letter-spacing: -1.2px; margin: 0 0 24px; text-wrap: balance; }
.research-authors { margin: 0 0 6px; font-weight: 550; }
.doc .research-affiliations { font-size: 13px; color: var(--muted); margin: 0 0 6px; }
.doc .author-note { font-size: 12px; color: var(--muted); margin: 0 0 16px; }
.research-header .meta { margin: 0 0 14px; }
.research-header .post-tags { margin: 0 0 18px; }
.research-links { display: flex; gap: 12px; flex-wrap: wrap; }
.research-links a { border: 1px solid var(--line); padding: 7px 15px; border-radius: 6px; color: var(--ink); font-size: 14px; background: var(--surface); }
.research-links a:first-child { background: var(--accent); color: var(--bg); border-color: var(--accent); }
.research-links a:hover { text-decoration: none; border-color: var(--accent); }
.research-links a span { padding-left: 10px; }
.research-links .resource-pending { display: inline-flex; align-items: center; border: 1px dashed var(--line); padding: 7px 15px; border-radius: 6px; color: var(--muted); font-size: 14px; }
.article-layout { display: grid; grid-template-columns: 190px minmax(0, 1fr); gap: 48px; align-items: start; }
.article-body { min-width: 0; }
.article-body img { max-width: 100%; height: auto; }
.reserved-figure > img { display: block; width: 100%; }
.article-figure { margin: 28px 0; border: 1px solid var(--line); border-radius: 8px; overflow: hidden; background: #fff; }
.article-figure .figure-link { display: block; cursor: zoom-in; }
.article-figure img { display: block; width: 100%; height: auto; }
.article-figure figcaption { display: flex; flex-wrap: wrap; align-items: baseline; justify-content: space-between; gap: 6px 18px; margin: 0; padding: 12px 16px; border-top: 1px solid var(--line); background: var(--surface); line-height: 1.5; }
.article-figure figcaption span { flex: 1 1 220px; }
.article-figure figcaption a { white-space: nowrap; }
.article-body > p { margin: 16px 0; }
.article-body h2 { scroll-margin-top: 24px; line-height: 1.3; }
.article-toc { position: sticky; top: 28px; font-size: 13px; line-height: 1.5; padding-top: 10px; max-height: calc(100vh - 56px); overflow-y: auto; scrollbar-width: thin; }
.article-toc > p { font-size: 11px; letter-spacing: 1px; text-transform: uppercase; font-weight: 650; color: var(--muted); margin: 0 0 14px; }
.article-toc .toc { background: transparent; border: 0; border-radius: 0; padding: 0; margin: 0; }
.article-toc ul { list-style: none; padding: 0; margin: 0; }
.article-toc li { font-size: 13px; margin: 0 0 12px; }
.article-toc ul ul { padding: 10px 0 0 12px; }
.article-toc a { color: var(--muted); display: block; border-left: 2px solid var(--line); padding-left: 12px; }
.article-toc a:hover, .article-toc a:focus-visible { color: var(--accent); border-color: var(--accent); text-decoration: none; }
.research-tldr { border-left: 3px solid var(--accent); padding: 20px 24px; background: var(--accent-soft); }
.research-tldr .eyebrow { display: block; margin: 0 0 8px; }
.research-tldr p { margin: 0; }
.case-metrics { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; margin: 24px 0; }
.case-metrics > div { padding: 16px 14px; background: var(--accent-soft); border-radius: 6px; }
.case-metrics strong { display: block; color: var(--accent); font-size: clamp(17px, 2.1vw, 24px); line-height: 1.3; font-variant-numeric: tabular-nums; }
.case-metrics span { display: block; margin-top: 6px; font-size: 12px; color: var(--muted); line-height: 1.5; }
.case-detail { margin: 20px 0; }
.case-detail summary { cursor: pointer; color: var(--muted); font-size: 14px; }
.case-detail .article-figure { margin-bottom: 12px; }
.reserved-figure { border: 1px solid var(--line); background: var(--surface); border-radius: 8px; overflow: hidden; margin: 28px 0; }
.figure-space { min-height: 260px; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 14px; padding: 28px; text-align: center; background-image: radial-gradient(var(--line) 1px, transparent 1px); background-size: 18px 18px; }
.figure-space strong { font-size: 20px; line-height: 1.4; max-width: 480px; font-weight: 550; }
.figure-space > span:last-child { font-size: 13px; color: var(--muted); background: var(--bg); padding: 3px 10px; }
.slot-index { font-size: 11px; letter-spacing: 1px; font-weight: 600; color: var(--accent); }
.method-slot .figure-space { min-height: 320px; }
.reserved-figure figcaption { margin: 0; padding: 12px 16px; border-top: 1px solid var(--line); line-height: 1.5; }
.article-body table { font-variant-numeric: tabular-nums; line-height: 1.5; }
.article-body th, .article-body td { padding: 12px; }
.article-body td:first-child { white-space: nowrap; }
.evaluation-note { margin: 20px 0; padding: 14px 18px; background: var(--code-bg); border-radius: 6px; font-size: 14px; }
.evaluation-note summary { cursor: pointer; font-weight: 550; }
.evaluation-note p { font-size: 14px; line-height: 1.7; margin-bottom: 0; }
.comparison-key { display: flex; flex-wrap: wrap; gap: 8px 20px; font-size: 12px; color: var(--muted); margin: 24px 0 14px; }
.comparison-key span { display: inline-flex; align-items: center; gap: 6px; }
.comparison-key i { width: 10px; height: 10px; display: inline-block; border-radius: 2px; }
.baseline-key { background: var(--chart-muted); }
.ours-key { background: var(--accent); }
.comparison-chart { border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); padding: 16px 0; }
.comparison-row { display: grid; grid-template-columns: 46px minmax(0, 1fr) 80px; gap: 14px; align-items: center; padding: 12px 0; font-variant-numeric: tabular-nums; }
.comparison-row > strong { font-size: 13px; }
.comparison-row > b { font-size: 13px; text-align: right; color: var(--accent); font-weight: 600; }
.bar-pair { display: grid; gap: 6px; }
.result-bar { position: relative; height: 27px; background: var(--code-bg); border-radius: 3px; }
.result-bar::before { content: ''; position: absolute; inset: 0 auto 0 0; width: var(--value); border-radius: 3px; }
.baseline-bar::before { background: var(--chart-muted); }
.ours-bar::before { background: var(--accent); }
.result-bar span { position: relative; display: inline-block; margin: 3px 0 0 6px; padding: 0 4px; font-size: 11px; font-weight: 600; line-height: 21px; background: var(--surface); color: var(--ink); border-radius: 2px; }
.case-reserve { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 14px; margin: 28px 0; }
.case-stage { min-width: 0; border-top: 2px solid var(--line); padding-top: 12px; }
.case-image-space { min-height: 155px; display: flex; align-items: center; justify-content: center; font-size: 12px; color: var(--muted); margin: 12px 0; padding: 16px; text-align: center; border: 1px dashed var(--line); border-radius: 4px; background: var(--surface); }
.case-stage h3 { font-size: 15px; margin: 12px 0 6px; line-height: 1.4; }
.case-stage p { font-size: 13px; line-height: 1.6; color: var(--muted); margin: 0; }
.routing-explorer { margin: 28px 0 12px; padding: 24px; border: 1px solid var(--line); border-radius: 10px; background: var(--surface); }
.explorer-toolbar { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: center; gap: 16px; padding-bottom: 20px; border-bottom: 1px solid var(--line); }
.explorer-splits { display: flex; gap: 4px; background: var(--code-bg); padding: 4px; border-radius: 7px; }
.explorer-splits button { appearance: none; border: 0; border-radius: 4px; padding: 7px 12px; background: transparent; font: inherit; font-size: 13px; cursor: pointer; color: var(--muted); }
.explorer-splits button[aria-pressed="true"] { background: var(--accent); color: var(--bg); }
.explorer-metric { display: flex; align-items: center; gap: 8px; font-size: 12px; color: var(--muted); }
.explorer-metric select { font: inherit; font-size: 13px; padding: 8px 28px 8px 10px; border: 1px solid var(--line); border-radius: 5px; background: var(--surface); color: var(--ink); max-width: 200px; }
.explorer-heading { display: flex; align-items: baseline; justify-content: space-between; flex-wrap: wrap; gap: 8px; margin-top: 22px; }
.explorer-title { font-size: 20px; font-weight: 600; letter-spacing: -0.3px; }
.explorer-direction { font-size: 12px; color: var(--muted); }
.explorer-legend { display: flex; flex-wrap: wrap; gap: 10px 20px; margin: 10px 0 24px; color: var(--muted); font-size: 12px; }
.explorer-legend span { display: inline-flex; align-items: center; gap: 6px; }
.explorer-legend i { display: inline-block; width: 9px; height: 9px; border-radius: 2px; }
.explorer-bars { display: grid; gap: 24px; padding: 0 0 20px; }
.explorer-bar-row { display: grid; grid-template-columns: 155px minmax(0, 1fr) 98px; align-items: center; gap: 14px; min-height: 32px; }
.explorer-method-name { font-size: 13px; color: var(--muted); }
.is-ours .explorer-method-name { color: var(--accent); font-weight: 650; }
.explorer-bar-track { display: block; height: 15px; border-radius: 3px; background: var(--code-bg); overflow: hidden; }
.explorer-bar-fill { display: block; height: 100%; border-radius: 3px; background: var(--chart-muted); }
.is-ours .explorer-bar-fill { background: var(--accent); }
.explorer-value { display: flex; align-items: center; justify-content: flex-end; gap: 6px; font-size: 13px; font-variant-numeric: tabular-nums; white-space: nowrap; }
.explorer-best { color: var(--good); font-size: 10px; border: 1px solid var(--line); padding: 1px 4px; border-radius: 3px; }
.doc .explorer-status { margin: 0; font-size: 12px; color: var(--muted); }
.doc .explorer-caveat { font-size: 12px; color: var(--muted); border-top: 1px solid var(--line); padding-top: 14px; margin: 14px 0 0; line-height: 1.65; }
.doc .chart-source { font-size: 12px; color: var(--muted); line-height: 1.7; margin: 10px 0 20px; }
.routing-details { margin: 20px 0 28px; }
.routing-details summary { font-size: 14px; cursor: pointer; color: var(--muted); }
.routing-details[open] summary { margin-bottom: 12px; }
button:focus-visible, select:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }
a:focus-visible, summary:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }
@media (max-width: 900px) {
  .article-layout { display: block; }
  .article-toc { position: static; margin-bottom: 28px; border-bottom: 1px solid var(--line); padding-bottom: 18px; max-height: none; overflow: visible; }
  .article-toc ul { display: flex; flex-wrap: wrap; gap: 8px 18px; }
  .article-toc li { margin: 0; }
  .article-toc a { padding-left: 8px; }
  .article-body { max-width: 760px; }
}
@media (max-width: 600px) {
  .research-header { margin-top: 36px; }
  .research-header h1 { font-size: 32px; letter-spacing: -0.6px; }
  .research-tldr { padding: 16px 18px; }
  .figure-space { min-height: 220px; padding: 20px; }
  .method-slot .figure-space { min-height: 260px; }
  .figure-space strong { font-size: 18px; }
  .comparison-row { grid-template-columns: 38px minmax(0, 1fr) 68px; gap: 8px; }
  .comparison-row > b { font-size: 11px; }
  .case-reserve { grid-template-columns: 1fr; gap: 24px; }
  .case-image-space { min-height: 200px; }
  .routing-explorer { padding: 16px; }
  .explorer-toolbar { gap: 12px; }
  .explorer-splits { flex: 1 1 100%; justify-content: space-between; }
  .explorer-splits button { flex: 1; padding: 7px 8px; }
  .explorer-metric { justify-content: space-between; width: 100%; }
  .explorer-title { font-size: 18px; }
  .explorer-bar-row { grid-template-columns: minmax(0, 1fr) 100px; gap: 8px; }
  .explorer-method-name { grid-column: 1; }
  .explorer-value { grid-column: 2; grid-row: 1; }
  .explorer-bar-track { grid-column: 1 / -1; grid-row: 2; }
  .explorer-bars { gap: 18px; }
}